The invention concern a jet regulator and aerator for attachment he sanitary fittings or the like, with a jet dispersion arrangement including a perforated plate that contains a number of flow holes, which produce individual jets.
A jet regulator of the above described type is already known from DE-PS 30 00 799, which has a perforated plate with a number of flow holes, produce individual jets. The perforated plate of this know jet regulator contains air intake device as well as several jet radiating strainers, which are located downstream in the flow direction. However, the arrangement of a large number of jet regulating strainers is expensive. Good jet regulator are also required to keep any calcification, particularly of the sensitive jet regulating strainers, moderately low. The perforated plate of the jet regulator known from DE-PS 30 00 799 is therefore designed to favor good jet dispersion, and the regulating strainers can be constructed with a correspondingly large mesh. Large mesh regulating strainer keep the danger of clogging and calcification comparatively low.
Another jet regulator has also been created, which contains a first and an immediately following second perforated plate (see DE-OS 34 04 662). The first and the separate second perforated plate contain flow holes, which are staggered with respect to each other. While the first perforated plate is designed to produce individual jets, the second perforated plate produces turbulence in these individual jets, creating the partial vacuum needed to mix in air and slow the individual jets down. Instead of the usual jet regulating strainers, the second perforated plate contains several ring walls placed downstream in the flow direction, which have circular steps or gradations on the inside and outside of the wall sections facing the perforated plates. These steps, which protrude into the paths of the individual jets produced by the perforated plates, are designed to properly disperse the water jets by mixing air into them. Since this known jet regulator does not require any jet regulating strainer, the danger of calcification is eliminated.
However, the jet regulator known from DE-OS 34 04 662 is comparatively large in height, requiring a special housing which can also limit the use of this jet regulator. Furthermore the production and assembly of the two perforated plates requires high accuracy, especially if they have several flow holes that are staggered with respect to each other, which involves considerable expense. To develop low noise in these perforated plates, the flow holes of the first perforated plate must have very sharp edges on their inflow side for example. Such edges, at least such edges of durable nature, are difficult to achieve with injection molded products.
The task therefore exists to create a jet regulator of the above described kind that is not prone to calcification, which can be manufactured at comparatively lost cost, which makes possible the production of a uniform full stream with the lowest possible noise, and still does not exceed the usual height of such jet regulators.